Microbiological acceptance criteria, specifications of herbal drugs and herbal drug preparations in various pharmacopoeias: a global scenario.

PURPOSE: A pharmacopoeia is a compendium of guidelines and criteria for drug quality. It was established by a national or regional entity and has legal significance. This applies to administration of drugs in a particular nation or region. METHOD: In this study, the differences and similarities of microbiological acceptance criteria, specifications for microbial enumeration of herbal drugs and herbal drug preparations in 14 national and international pharmacopeias were investigated. RESULTS: It was found that 12 pharmacopeias have given separate microbial limits for total aerobic microbial count (TAMC) and total yeast and mold count (TYMC), and a list of specified microorganisms for which acceptance criteria are defined. However, similarities were noticed in Ph.Eur, Ph. Helv and, BP. Salmonella, and Escherichia coli are the most common pathogens specified for herbal preparations in which boiling water is added prior to use and for internal use in all Pharmacopoeias because they serve as indicators of potential contamination. CONCLUSION: From this study, it can be concluded that the differences in microbial limit tests and their acceptance criteria as specified in the various pharmacopoeias need to be harmonized. It will become a more convenient option for global drug manufacturers to import/export herbal drugs, and this would also eliminate the burden of performing various analytical methods and comply with different microbial acceptance criteria set by various pharmacopoeias. The comparative data obtained from this study will be used to develop strategies for revisions of pharmacopoeias in a harmonized manner with respect to microbiological acceptance criteria, specifications for microbial enumeration of herbal drugs and herbal drug preparations.

Inhibition of biosynthesis and activity of nitrogenase in Azospirillum brasilense Sp7 under salinity stress.

Azospirillum brasilense is a microaerophilic, plant growth-promoting bacterium, whose nitrogenase activity has been shown to be sensitive to salinity stress. Growth of A. brasilense in semi-solid medium showed that diazotrophic growth in N-free medium was relatively less sensitive to high NaCl concentrations (200-400 mM) than that in presence of NH4+. Increase in salinity stress to diazotrophic A. brasilense in the semi-solid medium led to the migration of the pellicle to deeper anaerobic zones. Assays of acetylene reduction and nifH- lacZ and nifA- lacZ fusions indicated that salinity stress inhibited nitrogenase biosynthesis more strongly than nitrogenase activity. Under salt stress, the amount of dinitrogenase reductase inactivated by ADP-ribosylation was strongly reduced, indicating that the dinitrogenase reductase ADP ribosyl transferase (DRAT) activity was also inhibited by increased NaCl concentrations. Movement of the pellicle to the anaerobic zone and inhibition of DRAT might be adaptive responses of A. brasilense to salinity stress under diazotrophic conditions. Supplementation of glycine betaine, which alleviates salt stress, partially reversed both responses.